What typically causes crypt melt?

[Tug]

I recently ran into a post that had this to say about an observation. I know that sudden changes in CO2 and lighting can be hard on plants, but what typically causes crypt melt?

I was giving that warning about CO2, crypts and very low light because I have never seen it mentioned anywhere else. I have seen it happen twice, and the second time I kept the CO2 high after the crypts started melting, and the melting continued day after day until most of the leaves were gone. My observation conflicts with articles by Ole Pedersen and others in The Aquatic Gardener that say that CO2 fertilization is nothing but good at all light levels. That may be true for the majority of aquarium plants, but I am convinced that these crypts (wendtii and cordata) are an exception.

 

[Gerryd]

Tug,

I am under the impression that crypts store nutrients internally to be used in times of need. When the environment changes (more or less light, ferts or c02, etc) the plants use these stores to get by this transition period. Using them up causes the plant to disintegrate as they are still not assimilating new stores....

Of course I could be completely and utterly incorrect. Such things have happened before.....

That being said, c. wendti especially should not melt that much even for bigger env changes. I have kept it for years and it has always done well, c02 or not..

 

[Tug]

Thank you G,
Cryptocoryne parva has been growing fine for me. Still, I would like to try C. wendtii some day.

 

[Gerryd]

Hi Tug,

C. wendti comes in a variety of shades and is usually readily available....

They can cost $4-6 each at the LFS for a few leaves, but if well cared for will soon grow very well. Once established it is very resilient...

Just note that they can easily get 10-12" tall and are not really a foreground plant...

 

[aquabillpers]

The only time that C. wendtii melted in my tanks was once (in 10 years) when I did a radical cleaning of a neglected tank. It melted in a day or two but within a month it was all back where it had been.

I think it would take more time than that for it to exhaust it's stored nutrients.

Bill

 

[Wet]

Like aquabillpers I've found Crypts melt when their environment changes or when they are uprooted, but C. wendtii one of the more resilient Crypts. I have never found a reason for melt either. I think this sensitivity to changes in this plant is one reason folks often say Crypts have personality. On a side note, I also think that type of poor adaptation to change (such as new planting or trimming) is why some folks argue about the difficulty of plants like Downoi and B. japonica and R. indica (aka Ammania sp. 'Bonsai') and so on: all are actually easy plants that can take a minute to recover from changes.

But maybe there is something more scientific. Regardless I think these types of plants in a scape suggest stability and a longer term tank, and I think it a plus when appreciating pics of gardens.

Just babbling thoughts...